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Full text of "The Cambridge Natural History"

SHOULDER BLADE

for or serve to push along the rapidly-moving body. Stronger
fixation is therefore a greater necessity posteriorly than anteriorly.
In any case, whatever the explanation, this important difference
exists.

The shoulder-blade of mammals is as a rule a much-flattened
bone  with  a  ridge  on the  outer surface known as   the   spine;

Fio. 25.óRight scapula of
Dog (Canis familiaris).
x £. a, Acromlon ; ctf,
prescapular fossa ; c,
coracoid; cb, coracoid or
anterior border ; ess, in-
dicates the position of
the coraco-scapular su-
ture, obliterated in adult
animals by the complete
ankylosis of the two
bones ; gb, glenoid or
posterior border ; gc$
glenoid cavity ; pf> post-
scapular fossa ; s, spine ;
$s, suprascapular border.
(From Flower's Oste-
ology.}

JST

FIG, 26.óRight scapula of
Red Deer (Oervzis elaphus").
x J. <x, Acroniion j <%/£ an-
terior or prescapular fossa;
<?, coracoid ; ye, glenoid
cavity ; pf, postscapular
fossa ; -s*, partially ossi-
fied suprascapular border.
(From Flower's Osteology.)

this ridge ends in. a freely-projecting process, the acromion,
from which a branch often arises known as the metacromian.
This gives a bifurcate appearance to the end of the ridge. TBe*
spine is less developed and the scapula is narrower in such
animals as the Dog and the Deer which simply run, and whose
fore-limbs therefore are not endowed with the complexity of
movement seen, for instance, in the Apes.
It has been pointed out that the area which lies in front of